CVE-2026-87798 LXD client recursive file pull allows directory escape via malicious VM agent
A malicious VM agent can exploit improper link resolution in LXD client file pulls to write files to arbitrary host paths, enabling privilege escalation.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-87798?
CVE-2026-87798 is a medium-severity path traversal vulnerability in Canonical LXD, published on 28 Sep 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
Improper link resolution in the recursive file pull feature of the LXD CLI client in Canonical LXD versions 4.0.2 up to 6.9 (fixed in 4.0.14, 5.0.10 and 5.21.8) on Linux allows an attacker with root access inside a virtual machine to write attacker-controlled files or directory trees to arbitrary paths on the client host, with the operator's privileges. The attacker does this by using a modified lxd-agent that returns inconsistent SFTP directory listings and Lstat results.
Weakness: CWE-59
Which versions are affected by CVE-2026-87798?
How do I fix CVE-2026-87798?
No fix has been published for CVE-2026-87798 yet. Limit exposure of the affected software until one is available.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-87798 being exploited?
There is no known exploitation of CVE-2026-87798 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-87798, GHSA-mr8v-hx34-hfvf, UBUNTU-CVE-2026-87798.